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author | Guo Ren <ren_guo@c-sky.com> | 2019-07-30 08:43:22 +0200 |
---|---|---|
committer | Guo Ren <ren_guo@c-sky.com> | 2019-07-31 05:05:25 +0200 |
commit | 7f80fe207de9602aaff028c79345caa68c90cd31 (patch) | |
tree | 4052003f821439f67f8be27a26c016075cf48e7d /arch | |
parent | csky: Fixup mb() synchronization problem (diff) | |
download | linux-7f80fe207de9602aaff028c79345caa68c90cd31.tar.xz linux-7f80fe207de9602aaff028c79345caa68c90cd31.zip |
csky: Fixup dma_alloc_coherent with PAGE_SO attribute
This bug is from commit: 2b070ccdf8c0 (fixup abiv2 mmap(... O_SYNC)
failed). In that patch we remove the _PAGE_SO for memory noncache
mapping and this will cause problem when drivers use dma descriptors
to control the transcations without dma_w/rmb().
After referencing other archs' implementation, pgprot_writecombine is
introduced for mmap(... O_SYNC).
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/csky/include/asm/pgtable.h | 10 | ||||
-rw-r--r-- | arch/csky/mm/ioremap.c | 6 |
2 files changed, 12 insertions, 4 deletions
diff --git a/arch/csky/include/asm/pgtable.h b/arch/csky/include/asm/pgtable.h index c429a6f347de..fc19ba446d62 100644 --- a/arch/csky/include/asm/pgtable.h +++ b/arch/csky/include/asm/pgtable.h @@ -258,6 +258,16 @@ static inline pgprot_t pgprot_noncached(pgprot_t _prot) { unsigned long prot = pgprot_val(_prot); + prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED | _PAGE_SO; + + return __pgprot(prot); +} + +#define pgprot_writecombine pgprot_writecombine +static inline pgprot_t pgprot_writecombine(pgprot_t _prot) +{ + unsigned long prot = pgprot_val(_prot); + prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED; return __pgprot(prot); diff --git a/arch/csky/mm/ioremap.c b/arch/csky/mm/ioremap.c index 8473b6bdf512..48531115fd9d 100644 --- a/arch/csky/mm/ioremap.c +++ b/arch/csky/mm/ioremap.c @@ -29,8 +29,7 @@ void __iomem *ioremap(phys_addr_t addr, size_t size) vaddr = (unsigned long)area->addr; - prot = __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | - _PAGE_GLOBAL | _CACHE_UNCACHED | _PAGE_SO); + prot = pgprot_noncached(PAGE_KERNEL); if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) { free_vm_area(area); @@ -51,10 +50,9 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, pgprot_t vma_prot) { if (!pfn_valid(pfn)) { - vma_prot.pgprot |= _PAGE_SO; return pgprot_noncached(vma_prot); } else if (file->f_flags & O_SYNC) { - return pgprot_noncached(vma_prot); + return pgprot_writecombine(vma_prot); } return vma_prot; |